Password Problems

hey all. i posted something similar to this earlier and the problem hasnt been fixed yet so i decided to go ahead and repost. Firstly i want my win xp machine to boot straight to the desktop, no passwords or anything. Ive already disabled the welcome screen and went through the "control userpasswords2" command with no success. My name is set as the system admin also. Ive tried using tweak-XP's auto login program but i get a message that either my password or domain are faulty. im not sure where i can find what the domain is but i know it cant be a password because i have none set. Basically when i turned off the welcome screen, a smaller box pops up instead with my username already typed in and then it asks for a password. if i hit enter, it goes straight to the desktop. When i talked with a dell tech, he said that i probably have missing files or something. i dont know. please help anyone!

adam s